17 blockchain platforms — a brief introduction

The open sourceBlockchain Security Controls (PT-BSC) defines a blockchain as a peer-to-peer network which timestamps records by hashing them into an ongoing chain of hash-based proof-of-work, forming a record that cannot be changed without redoing the proof-of-work. A blockchain can be permissioned, permission-less or hybrid.

On the other hand, a distributed ledger is defined as a peer-to-peer network, which uses a defined consensus mechanism to prevent modification of an ordered series of time-stamped records. Consensus mechanisms include Proof of stake, Federated Byzantine Agreement etc.